Overhead lighting sources have been used for centuries in providing illumination for living spaces, both personal and commercial. There is of course a great scope of variation in the size and configuration of these living spaces, and designing illumination sources which are adaptable within this great scope of variation is therefore also challenging. Living or commercial spaces are seldom strictly rectangular and often incorporate angles and corridors which can cause shadows and produce dimly lit areas, which may be undesirable for inhabitants and residents.
It is therefore advantageous to have a lighting system which is expandable, and which can be easily configured or re-configured to illuminated irregularly shaped areas, or areas in which the lighting needs may vary. A modular system which is expandable and adaptable may have great benefits when using illumination sources in living spaces.
One example of an illumination source which has become increasingly used in recent years is the LED. A Light-Emitting Diode (LED) is a semiconductor light source, which have many practical applications due to their longer lifetime, faster switching, smaller physical size, greater durability and higher energy efficiency. LEDs have many advantages over other illumination sources. LEDs are solid state devices and if operated at low currents and at low temperatures, are subject to very limited wear and tear. Typical lifetimes are estimated to be 35,000 to 50,000 hours of useful life, compared to 10,000 to 15,000 hours for fluorescent tubes, and 1,000-2,000 hours for incandescent light bulbs. LEDs are also less fragile than fluorescent and incandescent bulbs, and are less susceptible to damage by external vibration.
LEDs produce more light per watt than incandescent bulbs, and are ideal for use in applications that are subject to frequent on-off cycling, unlike fluorescent lamps that burn out more quickly when cycled frequently. LEDs can very easily be dimmed continuously unlike fluorescent lamps which require a certain threshold voltage to maintain illumination.
LEDs have been found to have significant environmental benefits compared to other alternatives. It has been estimated that a building's carbon footprint from lighting can be reduced by 68% by exchanging all incandescent bulbs for new LEDs. LEDs are also non-toxic compared to compact fluorescent, which contains traces of mercury. Organic light emitting diodes (OLEDs) can be produced that use an organic compound as the emitting layer material of the LED, which can be a polymer.
When confronting the challenge of illuminating irregular living spaces, it is of course possible to position independent fixtures wherever they are needed. However, there are advantages to having all the fixtures designed with a common appearance. Similar fixtures may also be more easily used to provide uniform lighting levels. Additionally, it may be desirable to have all the fixtures linked together electrically, so they may be programmed to operate together, to all turn on or off together in unison, or provide programmed levels of illumination together or in balance within the living space.
Thus, there are competing criteria in designing a lighting system. The system should be flexible enough to allow for a range of areas, dimensions and applications. These competing criteria are especially difficult to satisfy when a number of different lighting sources are used, each having its own weight and bulk considerations. It would be advantageous therefore to have a lighting system utilizing uniform lighting sources, which are still individually controllable. A unified look to the illumination system also has aesthetic advantages.
Thus, there is need for a modular lighting system that can be modified or configured to accommodate a variety of living space configurations, has individually controllable operation, and especially a system that utilizes LED illumination sources for longer life performance and energy efficiency.